This invention relates to the field of fiber reinforced composite materials produced by molding a thermosetting resin, such as an epoxy resin or polyester resin, which is reinforced with fibers, such as carbon fibers, aramid fibers (Kevlar), glass fibers, and others, and also to rubber vulcanization type, fiber reinforced composite materials, in which a rubber material is vulcanized to improve certain properties of such materials.
One object of the present invention is to provide a thermosetting resin based, fiber reinforced composite material which retains important characteristics found in such fiber reinforced composite materials, such as light weight, high strength and high rigidity, but which also has improved qualities not available at a satisfactory level in such conventional materials: chemical resistance, oil resistance, being airtight or waterproof, certain sealing properties, electrical insulating properties, vibration damping properties, etc. With such improved functions, materials according to the present invention can thereby overcome disadvantages associated with conventional fiber reinforced composite materials, such as restrictions on use, the structural shortcomings of the various products to which fiber reinforced composite materials are applied, being uneconomical, and so on.
A further object of the present invention is to provide a thermosetting resin-based, rubber vulcanization type, fiber reinforced composite material in which a rubber material is vulcanized in the thermosetting step of the molding stage for the thermosetting resin, in order to impart the various improved functions described above to the resulting composite material.
Conventionally, fiber reinforced composite materials, produced by reinforcing a thermosetting resin with fibers, have excellent characteristics, such as being light in weight, high in strength and high in rigidity, and thus are currently widely used as aircraft and automobile parts and materials.
However, since a fiber reinforced composite material is insufficiently strong in connection with concentrated loads and is inferior in its capacity to dampen vibrations, a separate reinforcing member is additionally provided in the composite material, for example, where such a concentrated load is applied. In the case of material subject to vibrations, conventionally, special measures are required to prevent the transmission of such vibrations, by using, for example, a vibration insulator 6 as shown in FIG. 1B. In FIG. 1, the fiber reinforced composite material is indicated at 1.
In the case of fiber reinforced composite materials using carbon fibers, the carbon fibers are good electrical conductors and, therefore, it may become necessary to take special precautions when such materials are used with electric wiring or used as electrical insulation, in order to prevent electrical leakage. For example, where a container 8 for an electric board 7 is formed using a carbon fiber reinforced composite material as shown in FIG. 2B, an insulating plate 9 interposed between the bottom of the container 8 and the electric board 7 is required.
Also, conventional fiber reinforced composite materials are inferior with regard to other qualities, such as chemical resistance, oil resistance, and being airtight or waterproof, and certain sealing properties.
Accordingly, for products requiring such functions, special measures must be taken. For example, as shown in FIG. 3B, a separate sealant 12 must be affixed to the sliding portion of a fiber reinforced composite material 11 where a member 10, such as a pipe, is inserted.